reconsider the fact that you might have a viral influenza
complicated by as yet untreated bacterial bronchitis
( from the very little information you posted).This explains the extreme fatigue
,the muscle and joint aches , the chills and productive cough.If after 3 days onset of cough you are not better,your doctor may consider adding a5 day course betalactam antibiotic if you are not allergic to penecillin.Meanwhile get bed rest
,drink lots of healthy fluids take analgesia and increase your intake of fresh fruit and veggies
Get well soon.